(function () {
    'use strict';

    var root = this;

    var has_require = typeof require !== 'undefined';

    var THREE = root.THREE || (has_require && require('three'));
    if (!THREE) throw new Error('MeshLine requires three.js');

    function MeshLine() {
        THREE.BufferGeometry.call(this);
        this.type = 'MeshLine';

        this.positions = [];

        this.previous = [];
        this.next = [];
        this.side = [];
        this.width = [];
        this.indices_array = [];
        this.uvs = [];
        this.counters = [];
        this._points = [];
        this._geom = null;

        this.widthCallback = null;

        // Used to raycast
        this.matrixWorld = new THREE.Matrix4();

        Object.defineProperties(this, {
            // this is now a bufferGeometry
            // add getter to support previous api
            geometry: {
                enumerable: true,
                get: function () {
                    return this;
                }
            },
            geom: {
                enumerable: true,
                get: function () {
                    return this._geom;
                },
                set: function (value) {
                    this.setGeometry(value, this.widthCallback);
                }
            },
            // for declaritive architectures
            // to return the same value that sets the points
            // eg. this.points = points
            // console.log(this.points) -> points
            points: {
                enumerable: true,
                get: function () {
                    return this._points;
                },
                set: function (value) {
                    this.setPoints(value, this.widthCallback);
                }
            }
        });
    }

    MeshLine.prototype = Object.create(THREE.BufferGeometry.prototype);
    MeshLine.prototype.constructor = MeshLine;
    MeshLine.prototype.isMeshLine = true;

    MeshLine.prototype.setMatrixWorld = function (matrixWorld) {
        this.matrixWorld = matrixWorld;
    };

    // setting via a geometry is rather superfluous
    // as you're creating a unecessary geometry just to throw away
    // but exists to support previous api
    MeshLine.prototype.setGeometry = function (g, c) {
        // as the input geometry are mutated we store them
        // for later retreival when necessary (declaritive architectures)
        this._geometry = g;
        // if (g instanceof THREE.Geometry) {
        //     this.setPoints(g.vertices, c);
        // } else
        if (g instanceof THREE.BufferGeometry) {
            this.setPoints(g.getAttribute('position').array, c);
        } else {
            this.setPoints(g, c);
        }
    };

    MeshLine.prototype.setPoints = function (points, wcb) {
        if (!(points instanceof Float32Array) && !(points instanceof Array)) {
            console.error('ERROR: The BufferArray of points is not instancied correctly.');
            return;
        }
        // as the points are mutated we store them
        // for later retreival when necessary (declaritive architectures)
        this._points = points;
        this.widthCallback = wcb;
        this.positions = [];
        this.counters = [];
        if (points.length && points[0] instanceof THREE.Vector3) {
            // could transform Vector3 array into the array used below
            // but this approach will only loop through the array once
            // and is more performant
            for (var j = 0; j < points.length; j++) {
                var p = points[j];
                var c = j / points.length;
                this.positions.push(p.x, p.y, p.z);
                this.positions.push(p.x, p.y, p.z);
                this.counters.push(c);
                this.counters.push(c);
            }
        } else {
            for (var j = 0; j < points.length; j += 3) {
                var c = j / points.length;
                this.positions.push(points[j], points[j + 1], points[j + 2]);
                this.positions.push(points[j], points[j + 1], points[j + 2]);
                this.counters.push(c);
                this.counters.push(c);
            }
        }
        this.process();
    };

    function MeshLineRaycast(raycaster, intersects) {
        var inverseMatrix = new THREE.Matrix4();
        var ray = new THREE.Ray();
        var sphere = new THREE.Sphere();
        var interRay = new THREE.Vector3();
        var geometry = this.geometry;
        // Checking boundingSphere distance to ray

        sphere.copy(geometry.boundingSphere);
        sphere.applyMatrix4(this.matrixWorld);

        if (raycaster.ray.intersectSphere(sphere, interRay) === false) {
            return;
        }

        inverseMatrix.getInverse(this.matrixWorld);
        ray.copy(raycaster.ray).applyMatrix4(inverseMatrix);

        var vStart = new THREE.Vector3();
        var vEnd = new THREE.Vector3();
        var interSegment = new THREE.Vector3();
        var step = this instanceof THREE.LineSegments ? 2 : 1;
        var index = geometry.index;
        var attributes = geometry.attributes;

        if (index !== null) {
            var indices = index.array;
            var positions = attributes.position.array;
            var widths = attributes.width.array;

            for (var i = 0, l = indices.length - 1; i < l; i += step) {
                var a = indices[i];
                var b = indices[i + 1];

                vStart.fromArray(positions, a * 3);
                vEnd.fromArray(positions, b * 3);
                var width = widths[Math.floor(i / 3)] != undefined ? widths[Math.floor(i / 3)] : 1;
                var precision = raycaster.params.Line.threshold + (this.material.lineWidth * width) / 2;
                var precisionSq = precision * precision;

                var distSq = ray.distanceSqToSegment(vStart, vEnd, interRay, interSegment);

                if (distSq > precisionSq) continue;

                interRay.applyMatrix4(this.matrixWorld); //Move back to world space for distance calculation

                var distance = raycaster.ray.origin.distanceTo(interRay);

                if (distance < raycaster.near || distance > raycaster.far) continue;

                intersects.push({
                    distance: distance,
                    // What do we want? intersection point on the ray or on the segment??
                    // point: raycaster.ray.at( distance ),
                    point: interSegment.clone().applyMatrix4(this.matrixWorld),
                    index: i,
                    face: null,
                    faceIndex: null,
                    object: this
                });
                // make event only fire once
                i = l;
            }
        }
    }
    MeshLine.prototype.raycast = MeshLineRaycast;
    MeshLine.prototype.compareV3 = function (a, b) {
        var aa = a * 6;
        var ab = b * 6;
        return (
            this.positions[aa] === this.positions[ab] &&
            this.positions[aa + 1] === this.positions[ab + 1] &&
            this.positions[aa + 2] === this.positions[ab + 2]
        );
    };

    MeshLine.prototype.copyV3 = function (a) {
        var aa = a * 6;
        return [this.positions[aa], this.positions[aa + 1], this.positions[aa + 2]];
    };

    MeshLine.prototype.process = function () {
        var l = this.positions.length / 6;

        this.previous = [];
        this.next = [];
        this.side = [];
        this.width = [];
        this.indices_array = [];
        this.uvs = [];

        var w;

        var v;
        // initial previous points
        if (this.compareV3(0, l - 1)) {
            v = this.copyV3(l - 2);
        } else {
            v = this.copyV3(0);
        }
        this.previous.push(v[0], v[1], v[2]);
        this.previous.push(v[0], v[1], v[2]);

        for (var j = 0; j < l; j++) {
            // sides
            this.side.push(1);
            this.side.push(-1);

            // widths
            if (this.widthCallback) w = this.widthCallback(j / (l - 1));
            else w = 1;
            this.width.push(w);
            this.width.push(w);

            // uvs
            this.uvs.push(j / (l - 1), 0);
            this.uvs.push(j / (l - 1), 1);

            if (j < l - 1) {
                // points previous to poisitions
                v = this.copyV3(j);
                this.previous.push(v[0], v[1], v[2]);
                this.previous.push(v[0], v[1], v[2]);

                // indices
                var n = j * 2;
                this.indices_array.push(n, n + 1, n + 2);
                this.indices_array.push(n + 2, n + 1, n + 3);
            }
            if (j > 0) {
                // points after poisitions
                v = this.copyV3(j);
                this.next.push(v[0], v[1], v[2]);
                this.next.push(v[0], v[1], v[2]);
            }
        }

        // last next point
        if (this.compareV3(l - 1, 0)) {
            v = this.copyV3(1);
        } else {
            v = this.copyV3(l - 1);
        }
        this.next.push(v[0], v[1], v[2]);
        this.next.push(v[0], v[1], v[2]);

        // redefining the attribute seems to prevent range errors
        // if the user sets a differing number of vertices
        if (!this._attributes || this._attributes.position.count !== this.positions.length) {
            this._attributes = {
                position: new THREE.BufferAttribute(new Float32Array(this.positions), 3),
                previous: new THREE.BufferAttribute(new Float32Array(this.previous), 3),
                next: new THREE.BufferAttribute(new Float32Array(this.next), 3),
                side: new THREE.BufferAttribute(new Float32Array(this.side), 1),
                width: new THREE.BufferAttribute(new Float32Array(this.width), 1),
                uv: new THREE.BufferAttribute(new Float32Array(this.uvs), 2),
                index: new THREE.BufferAttribute(new Uint16Array(this.indices_array), 1),
                counters: new THREE.BufferAttribute(new Float32Array(this.counters), 1)
            };
        } else {
            this._attributes.position.copyArray(new Float32Array(this.positions));
            this._attributes.position.needsUpdate = true;
            this._attributes.previous.copyArray(new Float32Array(this.previous));
            this._attributes.previous.needsUpdate = true;
            this._attributes.next.copyArray(new Float32Array(this.next));
            this._attributes.next.needsUpdate = true;
            this._attributes.side.copyArray(new Float32Array(this.side));
            this._attributes.side.needsUpdate = true;
            this._attributes.width.copyArray(new Float32Array(this.width));
            this._attributes.width.needsUpdate = true;
            this._attributes.uv.copyArray(new Float32Array(this.uvs));
            this._attributes.uv.needsUpdate = true;
            this._attributes.index.copyArray(new Uint16Array(this.indices_array));
            this._attributes.index.needsUpdate = true;
        }

        this.setAttribute('position', this._attributes.position);
        this.setAttribute('previous', this._attributes.previous);
        this.setAttribute('next', this._attributes.next);
        this.setAttribute('side', this._attributes.side);
        this.setAttribute('width', this._attributes.width);
        this.setAttribute('uv', this._attributes.uv);
        this.setAttribute('counters', this._attributes.counters);

        this.setIndex(this._attributes.index);

        this.computeBoundingSphere();
        this.computeBoundingBox();
    };

    function memcpy(src, srcOffset, dst, dstOffset, length) {
        var i;

        src = src.subarray || src.slice ? src : src.buffer;
        dst = dst.subarray || dst.slice ? dst : dst.buffer;

        src = srcOffset
            ? src.subarray
                ? src.subarray(srcOffset, length && srcOffset + length)
                : src.slice(srcOffset, length && srcOffset + length)
            : src;

        if (dst.set) {
            dst.set(src, dstOffset);
        } else {
            for (i = 0; i < src.length; i++) {
                dst[i + dstOffset] = src[i];
            }
        }

        return dst;
    }

    /**
     * Fast method to advance the line by one position.  The oldest position is removed.
     * @param position
     */
    MeshLine.prototype.advance = function (position) {
        var positions = this._attributes.position.array;
        var previous = this._attributes.previous.array;
        var next = this._attributes.next.array;
        var l = positions.length;

        // PREVIOUS
        memcpy(positions, 0, previous, 0, l);

        // POSITIONS
        memcpy(positions, 6, positions, 0, l - 6);

        positions[l - 6] = position.x;
        positions[l - 5] = position.y;
        positions[l - 4] = position.z;
        positions[l - 3] = position.x;
        positions[l - 2] = position.y;
        positions[l - 1] = position.z;

        // NEXT
        memcpy(positions, 6, next, 0, l - 6);

        next[l - 6] = position.x;
        next[l - 5] = position.y;
        next[l - 4] = position.z;
        next[l - 3] = position.x;
        next[l - 2] = position.y;
        next[l - 1] = position.z;

        this._attributes.position.needsUpdate = true;
        this._attributes.previous.needsUpdate = true;
        this._attributes.next.needsUpdate = true;
    };

    THREE.ShaderChunk['meshline_vert'] = [
        '',
        THREE.ShaderChunk.logdepthbuf_pars_vertex,
        THREE.ShaderChunk.fog_pars_vertex,
        '',
        'attribute vec3 previous;',
        'attribute vec3 next;',
        'attribute float side;',
        'attribute float width;',
        'attribute float counters;',
        '',
        'uniform vec2 resolution;',
        'uniform float lineWidth;',
        'uniform vec3 color;',
        'uniform float opacity;',
        'uniform float sizeAttenuation;',
        '',
        'varying vec2 vUV;',
        'varying vec4 vColor;',
        'varying float vCounters;',
        '',
        'vec2 fix( vec4 i, float aspect ) {',
        '',
        '    vec2 res = i.xy / i.w;',
        '    res.x *= aspect;',
        '	 vCounters = counters;',
        '    return res;',
        '',
        '}',
        '',
        'void main() {',
        '',
        '    float aspect = resolution.x / resolution.y;',
        '',
        '    vColor = vec4( color, opacity );',
        '    vUV = uv;',
        '',
        '    mat4 m = projectionMatrix * modelViewMatrix;',
        '    vec4 finalPosition = m * vec4( position, 1.0 );',
        '    vec4 prevPos = m * vec4( previous, 1.0 );',
        '    vec4 nextPos = m * vec4( next, 1.0 );',
        '',
        '    vec2 currentP = fix( finalPosition, aspect );',
        '    vec2 prevP = fix( prevPos, aspect );',
        '    vec2 nextP = fix( nextPos, aspect );',
        '',
        '    float w = lineWidth * width;',
        '',
        '    vec2 dir;',
        '    if( nextP == currentP ) dir = normalize( currentP - prevP );',
        '    else if( prevP == currentP ) dir = normalize( nextP - currentP );',
        '    else {',
        '        vec2 dir1 = normalize( currentP - prevP );',
        '        vec2 dir2 = normalize( nextP - currentP );',
        '        dir = normalize( dir1 + dir2 );',
        '',
        '        vec2 perp = vec2( -dir1.y, dir1.x );',
        '        vec2 miter = vec2( -dir.y, dir.x );',
        '        //w = clamp( w / dot( miter, perp ), 0., 4. * lineWidth * width );',
        '',
        '    }',
        '',
        '    //vec2 normal = ( cross( vec3( dir, 0. ), vec3( 0., 0., 1. ) ) ).xy;',
        '    vec4 normal = vec4( -dir.y, dir.x, 0., 1. );',
        '    normal.xy *= .5 * w;',
        '    normal *= projectionMatrix;',
        '    if( sizeAttenuation == 0. ) {',
        '        normal.xy *= finalPosition.w;',
        '        normal.xy /= ( vec4( resolution, 0., 1. ) * projectionMatrix ).xy;',
        '    }',
        '',
        '    finalPosition.xy += normal.xy * side;',
        '',
        '    gl_Position = finalPosition;',
        '',
        THREE.ShaderChunk.logdepthbuf_vertex,
        THREE.ShaderChunk.fog_vertex && '    vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );',
        THREE.ShaderChunk.fog_vertex,
        '}'
    ].join('\n');

    THREE.ShaderChunk['meshline_frag'] = [
        '',
        THREE.ShaderChunk.fog_pars_fragment,
        THREE.ShaderChunk.logdepthbuf_pars_fragment,
        '',
        'uniform sampler2D map;',
        'uniform sampler2D alphaMap;',
        'uniform float useMap;',
        'uniform float useAlphaMap;',
        'uniform float useDash;',
        'uniform float dashArray;',
        'uniform float dashOffset;',
        'uniform float dashRatio;',
        'uniform float visibility;',
        'uniform float alphaTest;',
        'uniform vec2 repeat;',
        '',
        'varying vec2 vUV;',
        'varying vec4 vColor;',
        'varying float vCounters;',
        '',
        'void main() {',
        '',
        THREE.ShaderChunk.logdepthbuf_fragment,
        '',
        '    vec4 c = vColor;',
        '    if( useMap == 1. ) c *= texture2D( map, vUV * repeat );',
        '    if( useAlphaMap == 1. ) c.a *= texture2D( alphaMap, vUV * repeat ).a;',
        '    if( c.a < alphaTest ) discard;',
        '    if( useDash == 1. ){',
        '        c.a *= ceil(mod(vCounters + dashOffset, dashArray) - (dashArray * dashRatio));',
        '    }',
        '    gl_FragColor = c;',
        '    gl_FragColor.a *= step(vCounters, visibility);',
        '',
        THREE.ShaderChunk.fog_fragment,
        '}'
    ].join('\n');

    function MeshLineMaterial(parameters) {
        THREE.ShaderMaterial.call(this, {
            uniforms: Object.assign({}, THREE.UniformsLib.fog, {
                lineWidth: { value: 1 },
                map: { value: null },
                useMap: { value: 0 },
                alphaMap: { value: null },
                useAlphaMap: { value: 0 },
                color: { value: new THREE.Color(0xffffff) },
                opacity: { value: 1 },
                resolution: { value: new THREE.Vector2(1, 1) },
                sizeAttenuation: { value: 1 },
                dashArray: { value: 0 },
                dashOffset: { value: 0 },
                dashRatio: { value: 0.5 },
                useDash: { value: 0 },
                visibility: { value: 1 },
                alphaTest: { value: 0 },
                repeat: { value: new THREE.Vector2(1, 1) }
            }),

            vertexShader: THREE.ShaderChunk.meshline_vert,

            fragmentShader: THREE.ShaderChunk.meshline_frag
        });

        this.type = 'MeshLineMaterial';

        Object.defineProperties(this, {
            lineWidth: {
                enumerable: true,
                get: function () {
                    return this.uniforms.lineWidth.value;
                },
                set: function (value) {
                    this.uniforms.lineWidth.value = value;
                }
            },
            map: {
                enumerable: true,
                get: function () {
                    return this.uniforms.map.value;
                },
                set: function (value) {
                    this.uniforms.map.value = value;
                }
            },
            useMap: {
                enumerable: true,
                get: function () {
                    return this.uniforms.useMap.value;
                },
                set: function (value) {
                    this.uniforms.useMap.value = value;
                }
            },
            alphaMap: {
                enumerable: true,
                get: function () {
                    return this.uniforms.alphaMap.value;
                },
                set: function (value) {
                    this.uniforms.alphaMap.value = value;
                }
            },
            useAlphaMap: {
                enumerable: true,
                get: function () {
                    return this.uniforms.useAlphaMap.value;
                },
                set: function (value) {
                    this.uniforms.useAlphaMap.value = value;
                }
            },
            color: {
                enumerable: true,
                get: function () {
                    return this.uniforms.color.value;
                },
                set: function (value) {
                    this.uniforms.color.value = value;
                }
            },
            opacity: {
                enumerable: true,
                get: function () {
                    return this.uniforms.opacity.value;
                },
                set: function (value) {
                    this.uniforms.opacity.value = value;
                }
            },
            resolution: {
                enumerable: true,
                get: function () {
                    return this.uniforms.resolution.value;
                },
                set: function (value) {
                    this.uniforms.resolution.value.copy(value);
                }
            },
            sizeAttenuation: {
                enumerable: true,
                get: function () {
                    return this.uniforms.sizeAttenuation.value;
                },
                set: function (value) {
                    this.uniforms.sizeAttenuation.value = value;
                }
            },
            dashArray: {
                enumerable: true,
                get: function () {
                    return this.uniforms.dashArray.value;
                },
                set: function (value) {
                    this.uniforms.dashArray.value = value;
                    this.useDash = value !== 0 ? 1 : 0;
                }
            },
            dashOffset: {
                enumerable: true,
                get: function () {
                    return this.uniforms.dashOffset.value;
                },
                set: function (value) {
                    this.uniforms.dashOffset.value = value;
                }
            },
            dashRatio: {
                enumerable: true,
                get: function () {
                    return this.uniforms.dashRatio.value;
                },
                set: function (value) {
                    this.uniforms.dashRatio.value = value;
                }
            },
            useDash: {
                enumerable: true,
                get: function () {
                    return this.uniforms.useDash.value;
                },
                set: function (value) {
                    this.uniforms.useDash.value = value;
                }
            },
            visibility: {
                enumerable: true,
                get: function () {
                    return this.uniforms.visibility.value;
                },
                set: function (value) {
                    this.uniforms.visibility.value = value;
                }
            },
            alphaTest: {
                enumerable: true,
                get: function () {
                    return this.uniforms.alphaTest.value;
                },
                set: function (value) {
                    this.uniforms.alphaTest.value = value;
                }
            },
            repeat: {
                enumerable: true,
                get: function () {
                    return this.uniforms.repeat.value;
                },
                set: function (value) {
                    this.uniforms.repeat.value.copy(value);
                }
            }
        });

        this.setValues(parameters);
    }

    MeshLineMaterial.prototype = Object.create(THREE.ShaderMaterial.prototype);
    MeshLineMaterial.prototype.constructor = MeshLineMaterial;
    MeshLineMaterial.prototype.isMeshLineMaterial = true;

    MeshLineMaterial.prototype.copy = function (source) {
        THREE.ShaderMaterial.prototype.copy.call(this, source);

        this.lineWidth = source.lineWidth;
        this.map = source.map;
        this.useMap = source.useMap;
        this.alphaMap = source.alphaMap;
        this.useAlphaMap = source.useAlphaMap;
        this.color.copy(source.color);
        this.opacity = source.opacity;
        this.resolution.copy(source.resolution);
        this.sizeAttenuation = source.sizeAttenuation;
        this.dashArray.copy(source.dashArray);
        this.dashOffset.copy(source.dashOffset);
        this.dashRatio.copy(source.dashRatio);
        this.useDash = source.useDash;
        this.visibility = source.visibility;
        this.alphaTest = source.alphaTest;
        this.repeat.copy(source.repeat);

        return this;
    };

    if (typeof exports !== 'undefined') {
        if (typeof module !== 'undefined' && module.exports) {
            exports = module.exports = {
                MeshLine: MeshLine,
                MeshLineMaterial: MeshLineMaterial,
                MeshLineRaycast: MeshLineRaycast
            };
        }
        exports.MeshLine = MeshLine;
        exports.MeshLineMaterial = MeshLineMaterial;
        exports.MeshLineRaycast = MeshLineRaycast;
    } else {
        root.MeshLine = MeshLine;
        root.MeshLineMaterial = MeshLineMaterial;
        root.MeshLineRaycast = MeshLineRaycast;
    }
}.call(this));
